Tic-tac-toe is a classic game for two players where players take turns marking an X or O on a 3x3 grid. The first player to get three marks in a row wins, either horizontally, vertically, or diagonally. If all nine squares are filled and no player has three marks in a row, the game ends in a tie.
> Tic-tac-toe is also known as noughts and crosses in Commonwealth English, and Xs and Os in Canadian or Irish English.
> Tic-tac-toe is a solved game, meaning that if both players play their best, the game will always result in a draw.